Definition of knife :
1. A sword or dagger.
2. An instrument consisting of a thin blade, usually of steel and having a sharp edge for cutting, fastened to a handle, but of many different forms and names for different uses; as, table knife, drawing knife, putty knife, pallet knife, pocketknife, penknife, chopping knife, etc..
3. Fig.: To stab in the back; to try to defeat by underhand means, esp. in politics; to vote or work secretly against ( a candidate of one's own party).
4. To cut or stab with a knife.
5. To prune with the knife.
cutter, miter, hunting, dirk, edge, toad-stabber, sabre, fish, bread, shiv, paring, guillotine, grapefruit, bit, cane, tongue, lingua, corn, natural language, dinner, kris, misericord, skinning, table, Boy Scout, snickersnee, dessert, stab, cake, glossa, point, pruning, poniard, palette, butter, skewer, breakfast, scalpel, pocket, razor, molding, putty, dig, skiver, switchblade, clasp, lancet, tickler, cutting edge, paper, ferrule, prod, skean, Swiss Army, oyster, Bowie, clapper, spit, excelsior, pigsticker, poke, whittle, bodkin, butcher, Buck, jab, surgical, chopping
tool (part of speech: noun)
grindstone, awl, pick, keyhole saw, buzz saw, jigsaw, bench drill, plane, claw hammer, spade, screwdriver, ripsaw, tire iron, circular saw, miter box, hammer, crowbar, hoe, table saw, lug wrench, chain saw, jointer, scythe, wrench, square, snips, calipers, jackknife, back saw, mallet, gouge, arc welder, crosscut saw, hedge trimmer, planer, lathe, sickle, drill, vise, scroll saw, axe, posthole auger, stapler, pliers, shears, punch, wrecking bar, spanner, cold chisel, auger, scissors, tin snips, hatchet, grapnel, trowel, shovel, radial arm saw, chisel, bow saw, pickax, file, wedge, ball-peen hammer, hacksaw, handsaw, tool, spoke shave, band saw, coping saw, level, emery wheel, edger, sledgehammer, monkey wrench, drill press, welder, pipe wrench, saw
weapon (part of speech: noun)
Colt, bullet, ammunition, arrow, blowpipe, ax, trigger, Sidewinder, Remington, carbine, Browning, battery, shell, artillery, stiletto, piece, torpedo, peashooter, heater, sword, rifle, firearm, flamethrower, missile, dagger, javelin, spear, shooter, handgun, broadsword, blowgun, ordnance, bayonet, machine gun, rocket, musket, bilbo, gun, machete, lance, weapon, bow and arrow, pistol, armament, revolver, blunderbuss, repeater, saber, cannon, club, mortar, luger, scimitar, mace, weaponry, bomber, muzzle, boomerang, Winchester, shotgun, rapier, claymore, cutlass, bazooka, howitzer